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If the taxpayer was away from his "tax home" four nights - that means - three full days, one day he departed and one day he returned - total five days.For three full day - we should use the regular standard meal allowance rates - in your example - $71 per day.Travel for days he departed and returned - .the regular standard meal allowance must be prorated.
You can do so by one of two methods.Method 1: You can claim 3/4 of the standard meal allowance.Method 2: You can prorate using any method that you consistently apply and that is in accordance with reasonable business practice.So in general you would use $71 * 3 = $213 - for full days he was away from home$71 * 3/4 * 2 = $106.5 for days he departed and returnedTotal $319.5
See for reference IRS publication 463, page 6 - right column - Travel for days you depart and return.http://www.irs.gov/pub/irs-pdf/p463.pdfYou can deduct the cost of your meals while away from home - but such deduction is subject to the 50% limit. The 50% limit applies to employees or their employers, and to self-employed persons (including independent contractors) or their clients, depending on whether the expenses are reimbursed.See for reference IRS publication 463, page 11 - middle column - 50% Limit.There are some exemptions from 50% limitation - see page 12
What if the taxpayer's actual costs were less than the per diem amount allowed ?
What if he is missing many receipts, but there is proof that he is at the vendor show by a travel log. He is a sub contractor to a Jewlery company who provides a schedule.